Fluoride is again being injected into the city of Goldsboro’s water, after city officials received a letter of reassurance from the state health director.

Fluoride injections stopped in June after concerns were raised by studies that indicated possible problems with possible lead contamination when fluoride interacted with chloramines in the water.

But those concerns were addressed and the city’s public utilities director Karen Brashear said she “flipped the switch” Tuesday to re-start the fluoride injections after receiving clearance from the state Division of Public Health.

In a letter faxed to Ms. Brashear, Leah Devlin, the state health director, wrote, “I urge you to restart the fluoridation in Goldsboro as soon as possible so that the citizens of Goldsboro will reap its well-documented benefits.”

Ms. Brashear had ordered the fluoride injections halted in June as a precautionary measure, until the effects on residents’ drinking water could be determined.

“We did not actually feel that we had seen any high lead levels in any of our testing that we had done,” Ms. Brashear said Tuesday. “But chances were minimal that fluorides and chloramines could cause lead leaching.

“We wanted to err on the side of being conservative until we got another opinion on it.”

Ms. Brashear said because the state has access to better resources and experts, it seemed appropriate to seek a directive from them.

In Ms. Devlin’s letter, she indicated several agencies with more research behind them were consulted.

“The Centers of Disease Control and Prevention, CDC, named community water fluoridation as one of the 10 leading public health measures of the 20th century,” she wrote. “Staff in the Oral Health Section routinely monitor the fluoridation literature.”

Regarding the study done on the correlation between leaching lead from plumbing fixtures, Ms. Devlin wrote that her office had also contacted fluoridation experts at the American Dental Association and received assurance “that there is no indication that chloramines coupled with community water fluoridation use increased levels of blood lead.”

Ms. Devlin said safe drinking water is a top public-health priority in North Carolina.

“If we ever identify any reason for concern in this regard, we will contact you immediately,” she wrote.

Ms. Brashear said her office was happy to get the go-ahead to continue fluoridation program.